The extent of Yu Kobayashi’s injury has been made clear, after Kawasaki Frontale revealed on Friday that he will need four weeks to recover from injury.

The 27-year-old was forced to withdraw from the Japan national team squad last Monday due to a knock to his right hamstring.

Kobayashi suffered the injury during Frontale’s 1-0 loss at Montedio Yamagata in the MEIJI YASUDA J1 League’s third matchday on 22 March.

The right winger had already scored one goal and recorded two assists this season, earning him a place in new coach Vahid Halilhodzic’s maiden Japan squad.

Nagoya Grampus star Kengo Kawamata, who was called up in Kobayashi’s stead, received his Samurai Blue debut when he started upfront in Japan’s 2-0 win over Tunisia last Friday.